Objective

Greater population life expectancy and consistent improvement in diagnostic techniques have increased the diagnosis of abdominal aortic aneurysms (AAAs) in the elderly population. The aim was to study the natural history of small (< 55 mm) incidental AAAs in octogenarian and nonagenarian patients to assess the need for follow up and/or invasive treatment.

Methods

This was a retrospective analysis of a prospective registry. Patients ≥ 80 years old at the time of diagnosis of a < 55 mm AAA in 1988–2018 were selected. Clinical and anatomical characteristics were registered. Patients were divided in three groups: 30 – 39 mm, 40 – 49 mm, and 50 – 54 mm AAA. The outcome variables were aorto-iliac rupture, AAA reaching a surgical threshold (≥ 55 mm), and death. A descriptive statistical analysis was performed and life tables, Kaplan–Meier curves, and uni- and multivariable Cox regression were used.

Results

Three hundred and ten patients were included, 256 (82.6%) men, with mean index age of 84.5 years (standard deviation [SD] 3.5), and median follow up of 37.9 months (interquartile range [IQR] 18.2 – 65.4). Eighteen (5.8%) AAAs ruptured; four of these patients were operated on and only one survived. Sixty-two (20%) AAA reached a surgical size; eight were repaired electively, with 0% early mortality. The survival rates were 81%, 70%, and 38% at one, two, and five years. The rupture rates were 1%, 2%, and 6% and the AAAs reaching surgical threshold were 1%, 4%, and 19% for the same time periods. AAA size < 40 mm was an independent protective factor from rupture (0.13; 95% confidence interval [CI] 0.03 – 0.48), reaching surgical threshold (0.08; 95% CI 0.04 – 0.16) and death (0.63; 95% CI 0.42 – 0.95).

Conclusion

The risk of late rupture of small incidental AAA diagnosed in octogenarian and nonagenarian patients is very small, especially when the AAA is < 40 mm in diameter. In contrast, global mortality is high. Conservative management seems sensible, with strict selection of the patients who would benefit from follow up and eventual repair.

中文翻译：

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西班牙北部八十多岁和九十多岁的患者中小型偶发腹主动脉瘤的结果

目标

更高的人口预期寿命和诊断技术的持续改进提高了老年人群腹主动脉瘤 (AAA) 的诊断率。目的是研究八十多岁和十多岁的患者中小型（< 55 毫米）偶发性 AAA 的自然病程，以评估随访和/或侵入性治疗的需要。

方法

这是对前瞻性注册的回顾性分析。选择了 1988-2018 年诊断为 < 55 mm AAA 时≥ 80 岁的患者。注册临床和解剖特征。患者被分为三组：30 – 39 毫米、40 – 49 毫米和 50 – 54 毫米 AAA。结果变量是主髂动脉破裂、AAA 达到手术阈值（≥ 55 mm）和死亡。进行了描述性统计分析，并使用了生命表、Kaplan-Meier 曲线和单变量和多变量 Cox 回归。

结果

包括 310 名患者，256 名 (82.6%) 男性，平均指数年龄为 84.5 岁（标准差 [SD] 3.5），中位随访时间为 37.9 个月（四分位距 [IQR] 18.2 – 65.4）。18 个 (5.8%) AAA 破裂；其中四名患者接受了手术，只有一名幸免于难。62 个 (20%) AAA 达到手术大小；8 例进行了选择性修复，早期死亡率为 0%。一年、两年和五年的存活率分别为 81%、70% 和 38%。同期的破裂率分别为 1%、2% 和 6%，达到手术阈值的 AAA 分别为 1%、4% 和 19%。AAA 尺寸 < 40 mm 是从破裂 (0.13; 95% CI 0.03 – 0.48)、达到手术阈值 (0.08; 95% CI 0.04 – 0.16) 和死亡 (0.63; 95% CI 0.42 – ) 的独立保护因素0.95）。

结论

在八十多岁和非十多岁的患者中诊断出的小偶然 AAA 晚期破裂的风险非常小，尤其是当 AAA 直径 < 40 mm 时。相比之下，全球死亡率很高。保守治疗似乎是明智的，严格选择将从随访和最终修复中受益的患者。